以R142b为工质的有机朗肯循环低温发电系统研究

研究了以R142b为循环介质、采用螺杆式膨胀机的低温热能有机朗肯循环发电系统.在热源温度低于80℃的条件下,膨胀机最大能量转化效率为6％,系统总效率5.16％.在系统膨胀效率达97％的情况下,传输能耗导致机械效率仅有48％-65％,因此系统总效率较低,但最大(火用)效率为32％.提高蒸发压力、降低冷凝压力是提升能量转化效率的根本途径.实验研究表明,降低膨胀机入口蒸汽干度对膨胀效率略有促进,主要由于少量液体参与膨胀减少了膨胀环节的渗漏,提高了膨胀效率.实验表明该低温热能发电系统可行,但系统效率较低,有待进一步优化提高.     

用于钙钛矿太阳能电池光阳极的TiO2/ZnTiO3复合物的制备与性能

利用溶胶-凝胶法制备一系列不同Zn/Ti物质的量比的TiO_2/ZnTiO_3复合粉体,并借助XRD分析粉末的晶体结构。将复合粉末制备成膜作为钙钛矿太阳能电池的光阳极,通过SEM表征复合膜的表面形貌,并对所组装电池的性能进行测试。结果显示,Zn/Ti物质的量比对电池的性能有很大影响,当n(Zn)∶n(Ti)=1∶6时,组装的太阳能电池光电转换效率最好。     

高效单晶硅太阳电池基区结构设计与参数优化

首先利用TCAD半导体器件仿真软件全面系统地分析了在不同少子寿命的情况下,基区电阻率对常规P型单晶硅太阳电池输出特性的影响。然后基于对仿真结果的分析,提出一种具有非均匀基区的单晶硅太阳电池结构,并对其输出特性进行了仿真研究。结果表明:当少子寿命一定时,存在最优的基区电阻率,使得常规电池的转换效率最大;随着少子寿命的减小,电池最优的基区电阻率减小;提高基区电阻率有利于常规电池长波段量子效率和短路电流的提高,但同时会降低电池的开路电压和填充因子;当少子寿命较低时,非均匀基区结构不具有提高常规电池转换效率的作用。但当少子寿命增大到一定值时,通过优化非均匀基区的表面浓度,非均匀基区结构可有效改善常规电池的电学性能。     

合成介质对PEDOT催化染料敏化太阳电池光阴极性能的影响

采用聚3,4-乙烯二氧噻吩(PEDOT)/FTO为对电极,研究了合成介质对循环伏安法电聚合制备的PEDOT/FTO对电极性能的影响。通过SEM、CV、EIS、Tafel曲线,并首次采用SECM方法对所制备的对电极的电催化性能进行了表征。结果表明:在LiClO4水溶液和1-丁基-3-甲基四氟硼酸盐离子液体(IL)中制备的光阴极具有良好的电催化性能。J-V测试曲线表明,在LiClO4水溶液和IL中制备的光阴极所组装的DSSC器件的光电转化效率分别达6.4%和6.6%,接近于同等条件下以Pt对电极构建的DSSC器件的光电转化效率。     

钙钛矿太阳能电池空穴传输材料的研究进展

钙钛矿太阳能电池具有工艺简单、可弯曲、应用前景广阔等优点。从2009年出现起,至今其效率从3.8%提高到了22%以上,引起了研究者的广泛关注。介绍了钙钛矿太阳能电池的基本结构和工作原理,概述了钙钛矿太阳能电池空穴传输材料的研究进展,着重介绍了无机空穴传输材料的研究进展。最后展望了钙钛矿太阳能电池未来的发展与商业化应用。     

Simplified Perovskite Solar Cell with 4.1% Efficiency Employing Inorganic CsPbBr3 as Light Absorber

Perovskite solar cells with cost‐effectiveness, high power conversion efficiency, and improved stability are promising solutions to the energy crisis and environmental pollution. However, a wide‐bandgap inorganic–semiconductor electron‐transporting layer such as TiO₂ can harvest ultraviolet light to photodegrade perovskite halides, and the high cost of a state‐of‐the‐art hole‐transporting layer is an economic burden for commercialization. Here, the building of a simplified cesium lead bromide (CsPbBr₃) perovskite solar cell with fluorine‐doped tin oxide (FTO)/CsPbBr₃/carbon architecture by a multistep solution‐processed deposition technology is demonstrated, achieving an efficiency as high as 4.1% and improved stability upon interfacial modification by graphene quantum dots and CsPbBrI₂ quantum dots. This work provides new opportunities of building next‐generation solar cells with significantly simplified processes and reduced production costs.     

The synthesis of nano-sized ZSM-5 zeolite by dry gel conversion method and investigating the effects of experimental parameters by Taguchi experimental design

In this study ZSM-5 Nano particles with high crystallinity were synthesized using a dry gel conversion technique. An L9 orthogonal array of the Taguchi method was applied to investigate the effect of synthesis parameters, such as crystallization time, gel drying temperature, molar composition of template (TPAOH) and water content in the crystallization stage on crystallinity and particle size of the ZSM-5 catalyst. The products were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Beside short crystallization time, the particle sizes were considerably smaller in comparison with those prepared using the hydrothermal method. The results showed that the particle size and crystallinity increased with increasing water content and crystallization time. The effects of gel drying temperature and molar composition of template were found to be more complex, however. Comparing to hydrothermal method, ZSM-5 samples synthesized with the dry gel conversion exhibited higher selectivity to gasoline than other hydrocarbons.     

导弹数字舵机多通道信号转换及传输系统设计

针对全数字电动舵机无法直接使用传统的模拟信号及数据传输过程中丢帧、串帧、等待时间过长等问题,设计了一种基于DSP的多通道信号转换及传输系统,该系统采用片外AD及DA转换器实现信号转换,并针对传统通信算法存在的弊端,提出新的方法,实时配置FIFO中断等级,实现存在扰动情况下的无丢帧、无串帧通信,且执行时间37μs,提高了系统的稳定性、实时性。     

掺(Ga,Si)银铝浆对n型TOPCon太阳能电池电性能的影响

银铝浆是新一代太阳能电池(n型TOPCon)的关键材料,但其金属化后在Si发射极表面形成很大且很深的“银铝尖钉”,尖钉易击穿p-n结造成短路,成为限制其应用的瓶颈。引入Si、Ga元素对银铝浆进行优化,分别制备了掺Si和掺Ga, Si的银铝浆,研究其对金属化区域暗态饱和电流密度J_0.metal、欧姆接触电阻R_c的影响机制。结果表明：掺入少量Si后,金属化区域未见明显“银铝尖钉”,说明掺Si后抑制了在浆料金属化时出现“银铝尖钉”的现象,对p-n结损伤较小,J_0.metal下降,开路电压V_oc上升,但是R_c增大。再掺入Ga组分后“银铝尖钉”明显变浅,数量变多,R_c下降,弥补了掺Si银铝浆欧姆接触差的弊端,有较高的电池转换效率;用扩散浓度测试仪(ECV)对发射极表层进行元素浓度分析,发现Ga分布于表层0～50 nm处,有利于改善欧姆接触。研究了Ga、Si的掺入量对银铝浆电性能的影响,电池转换效率最高达到24.68%,太阳能电池效率提升0.55%。